Question

If x is equal to minus Root over 2 is a zero of polynomial X square + root 2 X + k then find the value of k

Answer 1

this is your answer see it its true

Answer 2

$x {}^{2} + \sqrt{2} x + k = 0 \\ substitute \: the \: value \: of \: x \: in \: this \: equation \\ ( - \sqrt{2} ) {}^{2} + \sqrt{2} ( - \sqrt{2} ) + k = 0 \\ 2 - 2 + k = 0 \\ k = 0$